Upright-piano action.



Patented June 27, 1916.

A 7TOR/VEY8 WITNESSES UNITED STATES PATENT orr on.

ADOLF KLEIN, or NEWYOVRK, N. Y.

UPRIGHT-PIANO ACTION.

. Specification of Letters Patent. P t t d J 27 191 Application filed August a, 1915. Serial No. 43,388.

To allwhom it may concern: I

Be it known that I, ADoLr KLEIN, a citizen of the United States, and a resident of the city of New York, borough of Manhattan, in the county and State of New York, have invented a new and Improved Upright- Piano Action, of which the following is a full, clear, and exact description.

This invention relates to upright piano actions of a nature similar to the mechanism described and claimed in my copending application, Serial No. LGA-i0, filed July 17, 1915.

Among the objects of the present device is to improve the mechanism with respect to delicacyof adjustment and reliability of operation, all as will be more fully set forth and claimed in the following specification and illustrated in the accompanying drawings in which Figure 1 is a side elevation of the improved mechanism in normal inactive posi tion; and Fig. 2 is a view of the same in check.

Referring more particularly to the drawings, I show at 10 fragment of a stationary frame having a flange 11 to which is pivoted a hammer butt 12 carrying a hammer 13 through its shank 14.

The key mechanism is substantially the same as in known devices, and hence I show only the wippen 15 and the abstract 16. The wippen 15 is pivoted at 17 upon a wippen flange 18 carried by the lower edge of the frame 10. The front end of the wippen has a. rigid extension 19 to which is pivoted a jack 20 having a head 21 at its upper end and a forwardly extending toe 22 at its lower end. A spring 23 arranged between the too 22 and the front end of the wippen tends to cause the jack to swing rearwardly at its upper end.

At 2 1 I show a back check having a contact shoe 25 on the rear face of the lower end. This back check 2% is in the nature of a lever of the first class pivoted at 26 upon a lug 27 extending upwardly and forwardly from the hammer butt 12. Adjacent the lug and just above it is a shoulder 28 against which an adjustable stop 29 carried by the upper rear end of the back check is adapted to strike and whereby the swinging movement of the back check around the pivot 26, under the force of a spring 30, is limited. In devices of this character it is desirable to provide means including the back check to check the hammer in a positive position at a predetermined distance from the string S when the key is held down. It follows, therefore, that for the accommodation of different players or to adapt the actions to various types of instruments, it is necessary to provide means to vary the distances from the strings at which the hammers are checked. The back check 2a is provided with a forwardly and upwardly projected shoulder 24: adapted to engage an adjustable stop 31 carried by a stationary bar 32 just in front of the hammer mechanism. The force of the spring 30 tends to swing the lever 24 around its pivot 26, bringing the shoulder 24- toward the stop 31, until such swinging movement is limited by contact of the adjustable stop 29 against the shoulder 28.

, As in my other application above referred to, the head 21 of the jack bears upwardly against a rounded shoulder 12 of the hammer butt when the key is depressed whereby the hammer is given a rearward impulse causing it to strike the string. WVhen the hammer rebounds, however, it is caught by the head 21 in the position shown in Fig. 2, said head acting as a wedge between the shoulder 12 on the one side and the shoe 25 on the other, while movement of the hammer butt around its pivot 33 is positively resisted by means of the stop 31. During the novement downwardly of the jack when the key is released, the hook 34: at the rear end of the head caused to glide along the front face of the hammer butt, by virtue of the spring 23, and hence will insure the forward movement of the hammer by engagement with an upwardly projecting hook 35 carried by the heel 36 of the hammer butt; An adjustable stop 37 carried by the jack is adapted to engage against the front face of the heel and limit the relative movement between the jack and the hammer butt.

I claim 1. The herein described upright piano action comprising, in combination, a hammer butt having a forwardly and upwardly projecting lug and having a shoulder above and in the rear of the lug, a back check includ ing a lever of the first class pivoted upon said lug, a spring acting between the hammer butt and the back check causing the upper end of the back check to approach said shoulder, an adjustable stop carried by the said upper end of the back check lever and adapted to abut against said shoulder V to limit the swinging movement of the back check lever with respect to the hammer butt, and a jack acting upwardly against the hammer butt to throw the same upwardly and rearwardly, said jack being adapted to wedge between the hammer butt and the back check lever to hold the parts in check.

2. In an upright piano action, the combination of a pivoted hammer butt, a back check lever pivoted intermediate of its ends to the hammer butt and having a shoulder at its middle portion, stop supported above and in front of the back check lever, means acting upon the back check lever tending to swing it around its pivot and bring its shoul der forwardly and upwardly toward said stop, means to limit this swinging tendency ADOLF KLEIN.

Witnesses:

GEO. L. BEELER, PHILIP D. RoLLHAUs.

0091c: of m; patent my be obtained tor an cent! each, by eddrenhai the ammunot hint, Washington. D. B." 

